Currently, a common camera shake compensation function of cameras is of an optical type that physically adjusts an optical axis. Among the optical-type camera shake compensation functions are those of a lens-shift type and an imaging element-shift type.
The lens-shift type camera shake compensation function is designed to move, with respect to an imaging element, part of a group of lenses where a subject image is formed, or all the lenses, in a direction that offsets camera shake by using a dedicated drive mechanism to correct an optical axis, thereby guiding the subject image to the imaging element (See Patent Document 1, for example).
However, in the case of the lens-shift type camera shake compensation function, for a group of lenses that is formed for each camera, the shape of a compensation lens or a drive mechanism that satisfies optical specifications need to be designed each time.
Meanwhile, the imaging element-shift type camera shake compensation function is designed to use a dedicated drive mechanism to move an imaging element in accordance with camera shake, thereby keeping the imaging element at a certain position relative to an optical axis of a group of lens (See Patent Document 2, for example).
However, even in the case of the imaging element-shift type camera shake compensation function, a dedicated drive mechanism needs to be designed each time to be suitable for an imaging element that is different for each camera.
Accordingly, what is proposed is one in which a compensation attachment is attached onto an optical axis of an optical lens (See Patent Document 3, for example): the compensation attachment has a power transmission mechanism including a movable prism, which refracts light entering an optical lens, a motor, which drives the movable prism, and a shaft, which transmits power of the motor to the movable prism.
As a result, there is no need to design the shape of a compensation lens and a drive mechanism for each camera, resulting in simplified design.